We have conducted a near-infrared monitoring campaign at the UK InfraRed Telescope (UKIRT), of the Local Group spiral galaxy M 33 (Triangulum). On the basis of their variability, we have identified stars in the very final stage of their evolution, and for which the luminosity is more directly related to the birth mass than the more numerous less-evolved giant stars that continue to increase in luminosity. In this fifth paper of the series, we construct the birth mass function and hence derive the star formation history across the galactic disc of M 33. The star formation rate has varied between ∼ 0.010 ± 0.001 (∼ 0.012 ± 0.007) and 0.060±0.005 (0.052±0.009) M ⊙ yr −1 kpc −2 statistically (systematically) in the central square kiloparsec of M 33, comparable with the values derived previously with another camera. The total star formation rate in M 33 within a galactocentric radius of 14 kpc has varied between ∼ 0.110 ± 0.005 (∼ 0.174 ± 0.060) and ∼ 0.560 ± 0.028 (∼ 0.503 ± 0.100) M ⊙ yr −1 statistically (systematically). We find evidence of two epochs during which the star formation rate was enhanced by a factor of a few -one that started ∼ 6 Gyr ago and lasted ∼ 3 Gyr and produced ≥ 71% of the total mass in stars, and one ∼ 250 Myr ago that lasted ∼ 200 Myr and formed ≤ 13% of the mass in stars. Radial star formation history profiles suggest that the inner disc of M 33 was formed in an inside-out formation scenario. The outskirts of the disc are dominated by the old population, which may be the result of dynamical effects over many Gyr. We find correspondence to spiral structure for all stars, but enhanced only for stars younger than ∼ 100 Myr; this suggests that the spiral arms are transient features and not part of a global density wave potential.

We present results from the first demonstration of a fully integrated SDN-controlled bandwidth-flexible and programmable SDM optical network utilizing sliceable self-homodyne spatial superchannels to support dynamic bandwidth and QoT provisioning, infrastructure slicing and isolation. Results show that SDN is a suitable control plane solution for the high-capacity flexible SDM network. It is able to provision end-to-end bandwidth and QoT requests according to user requirements, considering the unique characteristics of the underlying SDM infrastructure.

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Floating car data (FCD) has been used to collect traffic state information from a set of individual vehicles. Vehicles are equipped with On Board Units (OBU) that collect different measurements and the vehicle position and transmit the data to a remote control center. In current implementations of FCD systems, vehicle fleets use cellular connections for data transmission. In this paper we consider an IEEE 802.11p-based Road Side Unit (RSU) infrastructure for FCD collection. Installing RSUs in order to acquire perfect coverage may prove to be a costly solution, while gaps between the coverage areas will force data buffering at OBUs. This might be a viable solution for delay-tolerant, but not for safety-critical applications that require high data delivery ratio. The goal of this paper is to study the trade-offs between the size of the gaps between RSUs and other system parameters such as data delivery ratio, data collection update interval and size of measured data. We have proposed some heuristics that can be used while deciding on the distance between neighboring RSUs.

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